MXPA01001518A - Silo for storing and controlled supply of empty light containers, and method for using such silo - Google Patents

Abstract

Silo for the storage of light hollow bodies with controllable discharge, comprising a large deposit (1) provided with a discharge opening (2) at a lower part thereof, said opening being superimposed over an outlet conveyor belt (3) and also having a dispenser device (5) with first plate (6) and a second plate (7)which are hinged respectively to opposite walls of said deposit (1) by means of an axis (6a, 7a), said walls being downwardly inclined with respect to their articulation (6a, 7a) and with opposite slopes;said plates (6, 7) can overlap each other at their distal areas of the articulation thereby closing the bottom of the deposit (1) and/or separating from each other to form said opening (2) of given amplitude;pushing means (8, 9) actuated continuously or in jerks are associated to the plates (6, 7);a flap (11) is hingedly mounted next to the free end of said first plate (6) and is associated to pushing means (12).

Description

SILO FOR STORAGE AND REGULATED SUPPLY OF LIGHT PACKAGING EMPTY, AND METHOD FOR USING FIELD OF THE INVENTION The present invention concerns a silo for storing lightweight hollow bodies, specially designed (although its application may be generalized to other articles) to temporarily accumulate empty plastic containers / containers face to a later feeding of the same towards treatment lines (bottling, labeling, filling, etc.), whose silo is of the type that is provided with a loading opening at a high level and at a lower part of a gravity unloading opening of the containers, superimposed on a band Exit conveyor that links to a corresponding subsequent line of treatment or handling of said containers. This class of light, hollow bodies, such as empty, thin-walled plastic containers, when they are inside a large-capacity silo (for example a straight parallelepiped enclosure 4 meters by 5 meters high) fitted with an opening of discharge in the lower part, are highly prone to form "vaults" or "bridges" that impede the regular and continuous flow of said bodies by the corresponding discharge opening. This is because said bodies, for example containers, frequently have irregular shapes and are provided with protuberances such as handles, collars etc., which determine (in particular under the conditions of random distribution and pressure of the other overlapping containers) that they intertwine - between them forming a kind of structure, usually called "vault" or "bridge", which, leaning against the walls, causes a jam inside the silo, preventing the containers involved, and all those above it they, descend by the effect of gravity towards the lower part of the silo. Another limitation that empty light containers have for their storage in large silos resides in their relatively low resistance to crushing, either due to collisions caused by free fall from an excessive height or to the pressure exerted by the weight of a large amount of containers stacked above a particular container. This therefore limits the maximum free fall height from the top loading inlet as well as the maximum stack height of packages on a support surface, such as the bottom, within the silo. Another drawback of the aforementioned silos, especially if they are to store containers intended to be subsequently filled with liquids or beverages for human consumption, derives from the need for periodic cleaning of the interior of the silo, which is a burdensome task to deal with. of very large enclosures and of complicated access (generally only accessible through its upper opening, with elevating means or similar).

BACKGROUND OF THE INVENTION In the state of the art, different devices have been proposed to solve the problem of supplying by gravity other solid, compact bulk materials, such as mineral coal or gravel, which have propensity to form vaults. Thus, US 2,905,365 and US 3,286,886 disclose bulk material supply devices, or hoppers, both formed by a container of flat, rigid fixed walls of rectangular cross section, the area of which decreases from above. downwards, provided with an exit opening at the lower end. On the inside of at least one of said walls there is attached a flat, rigid plate, connected to means for applying to said plate a vibratory movement. This arrangement has the drawback that between the rigid plate and the wall of the hopper there is a space in which dirt particles tend to enter and accumulate. • that hinder the operation of the device, and that they are difficult to clean without disassembling the device. On the other hand, the transmission mechanisms of the vibratory movement, being arranged on the outside of the hopper, must pass through the corresponding fixed wall thereof to connect with the moving plate, which implies a relative complexity of said mechanisms. On the other hand, document WO 95/03233 discloses a hopper for the supply of bulk materials consisting of a frusto-conical container, the area of which section decreases from top to bottom, provided with an exit opening at one end lower. The wall of said container is formed by at least one fixed rigid portion, and by at least one movable rigid portion connected to vibration means generating means. This arrangement, while representing a certain simplification of mechanisms with respect to those mentioned above, has the disadvantage that the element that is vibrated is at least a substantial portion of the main wall of the container, which must be strong enough to withstand the pressure of the material and therefore have a relatively high mass, which involves a large energy expenditure. The devices described in the three aforementioned documents are useful for the supply of bulk, solid, compact materials, such as coal ore, gravel, etc., which are not susceptible to being damaged by knocks or crushing. However, such devices are not suitable for supplying bulk hollow, lightweight bodies, such as plastic containers, since these are liable to be crushed by the vibratory movement of the rigid plates, or rigid portions of the tank, in combination with the area of waning cross-section thereof, in addition to the weight of the hollow bodies themselves piled on top of one another in the interior of the silo, especially if it has a great height. Also known in the art of the sector, devices such as baffle plates, networks with sufficient through-openings for containers or labyrinths located at different levels within a high-rise silo intended to limit the maximum free fall height of a container over another container located at a lower level and the maximum height of piling containers on a particular container. However, said baffle plates, networks or labyrinths are an impediment to the free flow of stored articles that adds to the problem of the formation of "vaults" or "bridges". Other relevant background relating to the object of the invention are described in US-A-5,687,881 and WO-A-96/30727, EP-A-0336 815, EP-A-001576, EP-A-0336815 and US-A-4,127,970 BRIEF EXHIBITION OF THE INVENTION The invention provides a silo of great capacity, for temporary storage of hollow, lightweight bodies, whose emptying is performed by gravity, suitable in particular for accumulating said containers, coming for example from a production zone thereof, for a subsequent supply at the time when it is necessary to feed empty plastic containers, continuously, for example to bottling lines in which said containers will undergo different operations (labeling, filling, closing, etc.). With this, it is feasible to adapt the production characteristics of the machine or machines forming said containers, for example injection molding machines, to the needs of the bottling lines, during the operating cycles of the same. invention said silo is provided with means to regulate slopes that delimit the bottom of the silo, or apply to said bottom some vibrations or shakes to prevent the formation of "bridges" or "vaults", or in its case to facilitate its breakage Another object of the invention consists of a dispensing device adapted to deliver empty plastic containers to a conveyor belt, with a regular and controlled flow thereof, with the possibility of adapting to the characteristics of size and shape of said containers. of this invention is to provide a silo suitable for the storage of light hollow bodies, especially bottles d e empty plastic, the walls of said silo are easily washable, being able to be "moved" to the outside with what can be conveniently accessed at any point of the same.

Another objective of the present invention is to provide a silo for storage and regulated supply of empty light containers provided with means to limit the maximum free fall height of a container on another container located at a lower level and the maximum stacking height. of containers on a particular container, inside the silo. Finally, another objective of the present invention is to provide a method of storage and regulated supply of empty light containers by means of a silo equipped with the means mentioned in the two preceding paragraphs. According to an exemplary embodiment of the present invention related to the last-mentioned objective, a silo is provided for storage and regulated supply of empty light containers of the type comprising a large tank provided with a loading inlet at the top and a bottom with at least one discharge opening adjustable in its lower part, whose tank is filled and emptied by gravity. In order to limit the maximum height of free fall of a container on another container located at a lower level, as well as the maximum height of stacking of containers on a particular container, said silo comprises a subdivision of said deposit in superimposed enclosures, filled by gravity, the height of which is a function of the type of container to be stored, said enclosures being delimited by retractable support planes provided with independent driving means, capable of moving them to open or close at least one step to their through the unloading of containers from an enclosure to the lower immediate enclosure. In a preferred embodiment, said support plane comprises at least one flexible sheet, such as a tarpaulin, capable of being wound on a rotating core supported next to one of the side walls of said tank, with a front free edge of said sheet being flexible fixed to a load bar capable of moving away from and approaching said rotating core moving, supported and guided, in a predetermined path formed, for example, by a pair of lateral rails on which are supported corresponding wheels or skids fixed to both ends of said loading bar. Said predetermined trajectory, which preferably is horizontal, comprises retractable stops which prevent the recoil of the load bar in the extended position of the flexible sheet. The load bar is provided with thrust means comprising a pair of articulated arms, each of which is formed by two sections coupled together, each arm being articulated at one end to the bed, in an area close to the rotary core, and at the other end to the load bar, each of whose arms includes a tension spring fixed at one end to one of said sections and connected by a flexible element to the other of said sections so that it exerts on said We stretch a tendency to extend until they are aligned by pushing said load bar in the direction away from the said rotating core. An electric motor acts on said rotating core for and against said pushing means to, respectively, extend and collect said flexible sheet. The silo of the present invention optionally comprises side walls formed by canvases of flexible sheet endowed with reinforced peripheral edges, fixed to a support structure by means of tensors distributed along said edges. As a function of reinforcing said side walls, cables are arranged extending across the outer face of said canvases, fixed by means of tensioners to said support structure. In order to facilitate the manufacture, transport and assembly of said silo, taking into account its large dimensions, each of said support planes is associated with a portion of the structure of said tank constituting a stackable modular assembly to form a deposit, of a desired height, on a base module including said bottom and discharge opening, the modular assemblies being fixed to each other and to the base module at the final location by means of removable or permanent joints. Regardless of the type of execution chosen for the supporting planes, in the silo according to the present invention there are also provided means for detecting the level of containers accumulated on the support plane and / or on the bottom. Control means are susceptible, depending on signals received from said detection means, to act at least on said means of driving the support planes to regulate the flow of the containers from one to another enclosure and the maximum amounts of the same in each room. Optionally, said control means are integrated in a general control that governs the feeding of said silo and the regulated supply of containers from. the same towards, for example, a packaging line. The operation of said silo is carried out following the method of storage and regulated supply of empty light containers described below, which is also an objective of the present invention. With a silo as described above, the deposit of which is subdivided into overlapping enclosures by means of retractable support planes, whose enclosures are filled superiorly by gravity, said support planes being provided with independent means capable of selectively communicating with each other, in a desired moment, two of said enclosures, and the height of said enclosures being adequate to the minimum value of the maximum free fall height or the maximum stacking height capable of resisting a predetermined type of container without deteriorating, said method is characterized in that: the feeding of said deposit is always initiated by loading the enclosure located at a higher level when it is incommunicado with respect to the next / the discharge of any enclosure is always done by communicating it with the immediately lower enclosure being this empty, at least in part, and incommunicado respect to the next, except when the enclosure immediately below is the enclosure located at the lowest level, which is delimited inferiorly by said bottom and said adjustable discharge opening, in which case, said discharge opening may be: - closed, for storing containers / or - open at a selected extension, for a regulated supply of said containers. BRIEF EXPLANATION OF THE DRAWINGS These and other features will appear more clearly from the following detailed description of an exemplary embodiment that is provided with a purely illustrative, non-limiting intention, with respect to the accompanying drawings, in which; Fig. 1 is a partial elevational view showing the lower zone of the proposed silo, where the proposed dispensing device is installed; and Figs. 2 and 3 are respective elevational views, schematic, illustrative of the operation of the dispensing device that characterizes this invention. Fig. 4 is a vertical sectional view of a silo according to the invention, in a phase in which the complete filling with empty light containers is finished for temporary storage, with the lower opening closed by a mobile wing; Fig. 5 is an external elevation view of a side wall of a part of the silo of Fig. 4; Fig. 6 is a perspective view of an alternative embodiment of a support plane for a silo like that of Fig. 4; Fig. 7 is a top view of a preferred embodiment of a support plane of the silo of Fig. 4; Fig. 8 is a cross section taken along the line VIII-VTII of Fig. 7 with an enlarged detail; and Figs. 9 to 12 are schematic side views of the silo of Fig. 4 illustrating a possible filling / emptying sequence of said silo for a regulated supply of empty light containers. Fig. 13 is a simplified perspective view of a silo constructed according to the principles of the present invention; Fig. 14 is an enlarged detail illustrating the means of supporting the walls of the silo, and closing its corners; and Fig. 15 is another enlarged detail of means for tightening canvases defining said silo walls.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS As shown in said drawings, the proposed silo comprises a large reservoir 1 provided at a high level with a bulk loading opening of light hollow bodies, such as empty plastic containers or containers A, and a gravity unloading opening in a lower part where a dispensing device indicated generically by the reference 5 is installed, whose device is superimposed on an output conveyor belt 3 that links to a corresponding subsequent line of treatment or handling of said hollow bodies. According to the invention, the dispensing device 5 comprises a first plate 6 and a second plate 7, respectively articulated to opposite walls of said tank 1, by a horizontal axis 6a, 7a along one of its sides, whose plates 6, 7 are disposed oriented in descending inclination with respect to their articulation 6a, 7a and with opposite slopes, the first plate 6 extending, in part, below the free edge of the second plate 7 and said plates (6,7) being able to overlap, by its distal areas of the articulation, closing the bottom of the reservoir 1, and / or separating delimiting said discharge opening 2 of given amplitude, pre-selected according to the size and / or shape of the containers 1. As it is appreciated in Figures 1 and 3, the plates 6, 7 have associated thrust means 8, 9 of continuous or jerky action, so as to enable a simultaneous and coordinated tilting of said plates 6, 7 to adopt different inclinations. slope nations, maintaining during their displacements the said amplitude of passage of the discharge opening 2. The silo comprises a fixed structure 20, of rigid bars, which constitute frames that delimit a space in the form of a rectangular parallelepiped supporting the said device 5. The aforementioned pushing means 8, 9 for adjusting the inclination of the plates 6, 7, comprise an own drive assembly associated with each of said plates 6, 7. In the embodiment illustrated in the drawings each of said own drive assemblies constituting the pushing means 89 comprises a nut and spindle device 8a, 9a driven by an electric motor 8b, 9b associated respectively with each of said plates 6, 7 and independently controllable. It should be noted that the device would be equally operative with another type of mechanical drive, automatically controlled or even manually operated. As shown in FIG. 1, the second plate 7 is coupled by said articulation axis 7a to the cantilevered edge of a fixed wall, of downward inclination, forming a first ramp, firmly attached to said support structure 20 of the whole. Said first plate 6 has, mounted next to its free end, a wing 11, articulated on one of its sides to said first plate 6 and associated with its own pushing means 12, being able to adopt a pre-selected inclination orientation. , rising to a greater or lesser extent and being able to form a retainer wall of the containers A, as illustrated in FIG. 3 as opposed to the outlet opening 2 thereof. This facilitates the closing operations of the discharge opening of the silo without altering the slopes of the plates 6 and 7 of the bottom. In a preferred embodiment said wing 11 is oblong and of thin profile and is arranged attached on the upper face of a portion immediately to the free edge of the first plate 6, distal to the joint 6a, the portion of which has openings for the passage of fluidy dynamic cylinders constituting said pushing means 12, articulatedly attached to said first plate 6. The inclination of the first and second plates 6, 7, and that of the wing 11, as well as the application of any eventual shaking to one or more of they will be governed preferably from a central control unit according to a programmed sequence, adapted to the supply needs.

In Fig. 4 of the drawings, there is observed a silo according to an execution variant, of the present invention comprising a large reservoir 1 provided with a loading inlet 31 in the upper part, a bottom 32 with at least one discharge opening 2 adjustable in its lower part. Schematically and partially, a lifting device 30 for the upper loading of empty light containers A to said silo, and a conveyor belt 3, located immediately below the discharge opening 2 for the collection and transport of the containers supplied by the The container 1 is comprised of an internal subdivision into overlapping B-enclosures, filled by gravity, the height H of whose enclosures B is a function of the type of container A to be stored, in such a way that the maximum free fall height and the maximum crushing pressure supported by a container A located at a lower level are limited These enclosures are delimited by retractable support planes 33, provided with independent actuation means 34, 46, susceptible to move them to open or close at least one step through them for the unloading of containers A from an enclosure to the immediate enclosure ior, except the enclosure located at the lowest level, which is bounded by the bottom 32 and discharge opening 2. In Figs. 7 and 8 shows a preferred embodiment of a support plane 33 that is derived from an already classical system used in the sector of the manufacture of awnings, which have been made some simplifications and modifications, whose implementation is very favorable in economic terms . In fact, said support plane 33 comprises two flexible sheets 35, of a material such as a tarpaulin, capable of respectively winding on respective rotating cores 36 supported in opposing positions next to opposite side walls of said deposit 1. A front free edge of each flexible sheet 35 is fixed to a loading bar 37 capable of moving away from and approaching said rotating core 36 moving, supported and guided, in a predetermined trajectory. Said supported and guided trajectory constitutes one of the specific contributions of this embodiment that differ from the classic application in the sector of the awnings, and is formed by a pair of side rails 38 on which are supported some corresponding wheels 39 or skids fixed to both ends of said load bar 37. Preferably said rails 38 are horizontal, so that both flexible sheets are, when extended, coplanar, having retractable stops 40 in said predetermined path preventing backing of the loading bar 37. in a situation of extension of the flexible sheet 35. For a better explanation of the operation, in Figs. 7 and 8 one of said flexible sheets 35 is shown to be practically retracted (to the left with its extended position indicated by dashed line), while the other flexible sheet 35 is shown fully extended (to the right). However, usually both flexible sheets 35 will extend or retract in unison. The actuation of said flexible sheets 35 is as follows. Push means drive said load bars 37 in the direction away from the respective rotating cores 36, that is, towards a central area of the support plane 33. For their part, said drive means 34, which typically consist of an engine received inside each rotary core 36, act for and against the corresponding thrust means for, respectively, extend and collect said flexible sheets 35. The mentioned thrust means comprise, for each flexible sheet 35, a pair of arms articulated 41, each of which is formed by two sections 41a, 41b articulated to each other, each arm 41 being hingedly joined at one end to the bedframe, in an area close to the rotary core 36, and at the other end to the loading bar 37, each of whose arms 41 includes a tension spring fixed at one end to one of said sections 41a, 41b and connected by an element flexible to the other of said sections 41a, 41b so that it exerts on said sections 41a, 41b a tendency to extend until they are aligned, while the actuating means 34 act directly on said rotating core 36. In Fig. 6 a figure is shown. alternative embodiment for said supporting plane 33, which comprises at least one endless flexible band 16 extended between two rollers 43 supported in respective facing positions next to opposite side walls of said reservoir 1, and pressed by a pair of rollers of support 44 so that there are two superimposed sheets very close, whose flexible band 16 comprises a portion with a wide and extensive opening 45, there being a medium actuators 46 connected to rotate at least one of the rollers 43 reciprocatingly so that said flexible band 16 is able to assume a position in which the entire opening 45 is in the lower sheet, the upper sheet constituting a plane of support and enclosure of the upper enclosure, and at least one position in which a part of said opening is in the upper sheet, superimposed on another part of said opening 45 that remains in the lower sheet, facilitating a passage therethrough for unloading of packages A from one enclosure to the lower immediate enclosure (position shown in Fig. 6). This embodiment can also be implemented preferably with two of said adjacent strips 16, arranged in a coplanar manner, for each support plane 33. In FIG. 5, one of the side walls of the silo, formed by a canvas 47 of a sheet of a flexible material, fixed by means of tensioners 48, distributed along its reinforced peripheral edges 49, to a supporting structure la. In order to reinforce said side walls, cables 22 have been arranged extending across the outer face of said canvases 47, fixed by means of tensioners 51 to said supporting structure. According to a variant of the invention, the silo is also characterized in that each of the support planes 33 described above is associated with a portion of the structure of said tank 1 (see again Fig. 4) constituting a modular assembly stackable to form a reservoir 1, of a desired height, on a base module including said bottom 32 and discharge opening 2, the modular assemblies being fixed together and with the base module at the final location by removable or permanent joints 52. The silo of the invention also comprises means for detecting the level of packages A accumulated on the support plane 33 and / or on the bottom 32 and control means capable of acting on said actuating means 34, 46 of the support planes 33 that divide said enclosures B based on signals received from said detection means. Said control means are integrated in a general control that governs the feeding of said silo and the regulated supply of packages A therefrom. In Figs. 9-12 illustrate the method of storage and regulated supply of empty light A packages of the invention, using a silo as described in Figs. 4 to 8, whose method is characterized in that it is acted upon by the actuation of the support planes 33 so that in no case a container A falls freely from a height greater than the height H of the enclosures, nor a container A support on top of he a height of containers stacked higher than said height H of the enclosures. As discussed above, the height H of said enclosures B has been defined to be suitable for the minimum value of the maximum free fall height or the maximum stacking height capable of withstanding a predetermined package type A without deteriorating. An example of a logical sequence for filling and emptying said silo for a regulated supply of empty light containers A is as follows: a) the supply of said tank 1 is initiated by loading the enclosure located at a higher level, being incommunicado with respect to the next one (Fig. 9); b) when the enclosure located at the highest level is full, or before, the flexible sheets 35 are actuated to remove the support plane 33 (Fig. 10) so that said enclosure located at a higher level communicates with the enclosure immediately below, the discharge of containers A occurring; it is an indispensable condition, in order to effect the unloading of any enclosure, that the immediately inferior enclosure is empty, at least in part, and incommunicado with the next, except when the immediately inferior enclosure is the enclosure located at lower level; c) if there are more than two overlapping B enclosures, the unloading of a particular enclosure on its immediately lower enclosure may be made simultaneously with the loading or unloading of an enclosure located at a higher level (see Fig. 11) provided that fulfill the indispensable condition mentioned in paragraph b); d) this procedure is repeated sequentially in a downward direction until the immediately lower enclosure is the enclosure located at the lowest level (Fig. 12), which is delimited internally by said bottom 32 and said adjustable discharge opening 2, in which case there are two alternatives: if what is desired is to use the silo as temporary storage of containers A) said discharge opening 2 is closed (Fig. 4) allowing the complete filling of the lower level enclosure; fl) then the flexible sheets are closed of the support plane 33 of the upper immediate enclosure to proceed to its complete filling, and so on in ascending order until the filling of all the enclosures is achieved (Fig. 4), or of a desired number of enclosures; or if what is desired is to use the silo for a regulated supply of containers A e2) said discharge opening 2 is open (Fig. 12) at a selected extension according to the flow, of containers required; and f2) then steps a) -d) are repeated continuously at a suitable rate to feed said required flow of containers through the discharge opening 2, whose rate can be automatically controlled from signals from a filling level sensor means of each enclosure. According to the embodiment of Figs. 13 to 15, the proposed silo comprises a large reservoir 1 provided with a discharge opening in a lower and upperly open part, delimited laterally by laminar walls 60 of a flexible material. Each of said laminar walls 60 comprises an endless canvas, for example a resistant canvas, stretched stretched, surrounding parallel drums 61, 62, at different levels, upper and lower, with the possibility of moving said canvas, by means of of a tractor device 63 associated to one of the drums 61, advantageously to the one located at lower level of each pair and the second drum 62, of free rotation, acting as a guide. Said tractor device 63 may be manually operated (such as the one shown, ie a crank, removable) or motorized. In addition, each laminar wall 60 has, at mid-height, a pair of rollers 64, 65 between which the aforesaid endless stretched canvas passes, one of whose rollers 65, located on the outside, is capable of traveling by rolling with support on the internal roller 6, in order to conveniently tension said canvas. In the example illustrated in the drawing, the silo comprises four laminar walls 60 delimiting a rectangular, quadrangular parallelepiped enclosure, with supporting members 67 provided with column profiles with two cross panels, the wings 68 of the dihedral being provided at the corners. external provide a support for the ends of the drums 61, 62 and rollers 64, 65 and the inner right angled wings 69 form an interspace closing corner between the canvases. The silo could have another section, for example pentagonal or of more sides, keeping all the functional characteristics explained, although in the case of the subdivision in floors a rectangular section will be adopted. In order to avoid the formation of obstructions by the aforementioned phenomenon of "vaults" or "bridges" it has been foreseen that one or more of said laminar walls 60 is connected to a mechanism generating vibratory or shaking movement, for example to a pneumatic cylinder or a thrust cam governed from a control center, through at least one connection point between said mechanism and the wall. From said control center it will also be possible to control the degree of tensioning of the laminar wall with vibrating means. In an alternative embodiment, which has not been illustrated, it has been foreseen to build the silo by means of a fixed structure, of rigid bars forming frames delimiting a parallelepiped shaped space supporting a dispensing device which provides said discharge opening, said bar structure further supporting said drums 61, 62 and rollers 64, 65 on which said laminar walls and said rollers extend. In this case, said laminar walls 60 will cover the spaces delimited by each frame, with the drums 61, 62 on the upper and lower sides thereof. The examples of embodiment and use described above are intended to be merely illustrative and not limiting, and a person skilled in the art may introduce numerous changes or modifications, both in the silo and in the method of use, without departing from the scope of the invention, which is defined by the appended claims.

Claims (33)

Claims

1. Silo for storage of light hollow bodies with adjustable discharge, in particular applicable to empty plastic containers (A), of the type comprising a large tank (1) provided with a loading opening (31), a bottom (32) with less a discharge opening (2) in a lower part, superimposed on an exit conveyor belt (3), characterized in that said discharge opening (2) integrates a dispensing device (5), which comprises at least a first plate ( 6) and a second plate (7), articulated respectively to opposite walls of said tank (1), by a horizontal axis (6a, 7a) along one of its sides, whose plates (6, 7) are arranged oriented in downward inclination with respect to its articulation (6a, 7a) and with opposite slopes, the first plate (6) extending, at least in part, below the free edge of the second plate (7) and said plates (6, 7) being able to overlap, by their distal areas of the joint, closing the bottom of the tank (1), and / or separating delimiting said discharge opening (2) of given amplitude, pre-selected according to the size and / or shape of the containers (1), the plates (6, 7) having associated thrust means (8, 9) of continuous or jerky action, so as to enable a simultaneous tilting and coordinate of the plates (6, 7) to adopt different slope inclinations, maintaining during said displacements the said amplitude of passage of the discharge opening (2).

2. Silo, according to claim 1, characterized by comprising a fixed structure (20) of rigid bars (21), which constitute frames (22) that define a space in the form of rectangular parallelepiped supporting the said dispensing device (5).

3. Silo, according to claim 2, characterized in that said second plate (7) is coupled, by said articulation axis (7a), to the cantilevered edge of a wall (10), fixed, downward inclined, attached to said structure (20) of the set support.

4. Silo, according to any one of the preceding claims, characterized in that said thrust means (8, 9) that allow adjusting the inclination of the plates (6, 7), comprise an own drive assembly associated with each of said plates (6, 9). , 7).

5. Silo, according to claim 4, characterized by each one of the own drive assemblies constituting the pushing means (8, 9) comprises a nut and spindle device (8a, 9a) driven by an electric motor (8b, 9b) associated respectively to each of said plates (6, 7) and independently controllable.

6. Silo, according to one of the preceding claims, characterized by at least said first plate (6) has, mounted next to its free end, a wing (11), hinged on one of its sides to said first plate (6) and associated to its own pushing means (12), being able to adopt a preselected inclination orientation, rising to a greater or lesser extent and being able to form a retainer wall of the containers (1) opposite to the opening (2) of exit of the same.

7. Silo, according to claim 6, characterized in that said wing (11) is oblong and of thin profile and is disposed attached on the upper face of a portion immediately to the free edge of the first plate (6), distal to the joint (6a) , the portion of which has passage openings for fluidynamic cylinders constituting said pushing means (12), hingedly attached to said first plate (6).

8. Silo according to any one of the preceding claims, characterized in that the inclination of the first and second plates (6, 7), and that of the wing (11), as well as the application of any possible shaking to one or more thereof, they govern from a central control unit according to a programmed sequence.

9. Silo, according to claim 1, characterized in that it also includes means to prevent damage to the containers (A) due to collisions by free fall from an excessive height and / or by a crush caused by an excessive stacking, whose means comprise a subdivision of said tank (1) in superimposed enclosures (B), filled from above by gravity, the height (H) of whose enclosures (B) is a function of the type of container (A) to be stored, so that the maximum height of free fall and the maximum pressure is limited of crushing supported by a container (A) at a lower level, said enclosures (B) being delimited by retractable support planes (33) provided with means for actuating (34, 46), independent, capable of moving them to open or closing at least one step through it for the unloading of containers (A) from one enclosure to the next lower enclosure, except for the enclosure located at the lowest level, which is delimited by the bottom (32) and unloading opening. a (2).

10. Silo, according to claim 9, characterized in that said support plane (33) comprises at least one flexible sheet (35), such as a tarpaulin, capable of being wound on a rotating core (36) supported next to one of the walls side of said tank (1), with a front free edge of said flexible sheet (35) fixed to a load bar (37) capable of moving away from and approaching said rotating core (36) moving, supported and guided, in a default path.

11. Silo, according to claim 10, characterized in that it comprises retractable stops (40) in said predetermined trajectory that prevent the recoil of the load bar (37) in the extended position of the flexible sheet (35).

12. Silo, according to claim 11, characterized in that said support plane (33) further comprises means for pushing said load bar (37) in the direction away from the rotating core (36), said actuating means (34) acting, such as an electric motor coupled to said rotary core (36), for and against said pushing means for, respectively , extending and collecting said flexible sheet (35).

13. Silo, according to claim 11, characterized in that said support plane (33) further comprises means for pushing said load bar (37) in the direction of the rotating core (36), said actuating means (34) acting in against and in favor of said pushing means for, respectively, extending and collecting said flexible sheet (35).

14. Silo, according to claim 12, characterized in that said pushing means comprise a pair of articulated arms (41), each of which is formed by two sections (41a, 41b) articulated to each other, each arm (41) being jointed hinged at one end to the bed, in an area close to the rotating core (36), and at the other end to the load bar (37), each of whose arms (41) includes a tension spring fixed by a end to one of said sections (41a, 41b) and connected by a flexible element to the other of said sections (41a, 41b) so that it exerts on said sections (41a, 41b) a tendency to extend until they are aligned.

15. Silo, according to claim 10, characterized in that said predetermined path comprises a pair of directly opposite lateral rails (38) on which are supported corresponding wheels (39) or runners fixed to both ends of said load bar (37).

16. Silo, according to claim 15, characterized in that said rails (38) are horizontal.

17. Silo, according to any of claims 10 to 16, characterized in that said support plane (33) comprises two of said flexible sheets (35), the corresponding rotating cores (36) being supported in respective facing positions together with side walls opposite of said tank (1), with the corresponding predetermined trajectories arranged so that the respective load bars (37) are mutually adjacent when said flexible sheets (35) are fully extended.

18. Silo, according to claim 9, characterized in that said support plane (33) comprises at least one endless flexible band (16) extended between two rollers (43) supported in respective facing positions next to opposite side walls of said reservoir (1), and pressed by a pair of support rollers (44) so that two very close superimposed sheets remain, whose flexible band (16) comprises a portion with a wide and extensive opening (45), there being a means of actuation (46) connected to rotate at least one of the rollers (43) back and forth so that said flexible band (16) is capable of adopting at least one position in which a part of said opening is in the upper sheet, superimposed on another part of said opening (45) remaining in the lower sheet, facilitating a passage therethrough for the unloading of containers (A) from an enclosure to the lower immediate enclosure.

19. Silo, according to claim 9, characterized in that it comprises side walls formed by canvases (47) of flexible sheet fixed, by means of tensioners (48) distributed along their reinforced peripheral edges (49), to a supporting structure (the) .

20. Silo, according to claim 19, characterized in that it also comprises, as a function of reinforcement of the walls, cables (50) extended across the outer face of said canvases (47), fixed by means of tensioners (51) to said support structure (la).

21. Silo, according to claim 9, 19 or 20, characterized in that each of said support planes (33) is associated with a portion of the structure of said tank (1) constituting a stackable modular assembly to form a tank (1). ), of a desired height, on a base module including said bottom (32) and discharge opening (2), the modular assemblies being fixed to each other and to the base module at the final location by removable or permanent joints (52).

22, Silo, according to claim 9, characterized in that it also comprises means for detecting the level of containers (A) accumulated on the support plane (33) and / or on the bottom (32) and susceptible control means to act at least on said drive means (34, 46) of the support planes (33) dividing said enclosures (B) as a function of signals received from said detection means.

23. Silo, according to claim 22, characterized in that said control means are integrated in a general control that governs the feeding of said silo and the regulated supply of containers (A) therefrom.

24. Silo, according to claim 1, characterized in that at least the upper area of the tank (1), above the region occupied by the said discharge opening, is delimited laterally by laminar walls (60) of a flexible material.

25. Silo, according to claim 24, characterized in that each of said laminar walls (60) comprises an endless canvas such as a resistant canvas, extended so as to surround two separate drums (61, 62), at different levels, upper and lower. lower, with the possibility of displacement of said canvas, by means of a tractor device (63) associated with one of the drums (61), and the second drum (62), with free rotation, acting as a guide.

26. Silo, according to claim 25, characterized in that each laminar wall (60) has associated, at half height, a pair of rollers (64, 65) between which pass the canvas pinched, one of whose rollers (65), located in the outside, it is susceptible to move rolling with support on the internal roller (6), in order to conveniently tighten said canvas.

27. Silo, according to claim 24, characterized in that it has a polygonal cross section and in the areas of juxtaposition of the flexible laminar walls (60) there are provided support members (67) constituted by cross-section column profiles, with wings (68) of the external dihedral forming a support for the ends of the drums (61, 62) and rollers (64, 65) and with the wings (69) at an interior right angle forming a corner of closure and protection of the inter -space between the canvases.

28. Silo, according to claim 24, characterized by comprising four laminar walls (60) delimiting a rectangular, quadrangular parallelepiped enclosure.

29. Silo, according to claim 24, characterized in that at least one of said laminar walls (60) is connected to a mechanism generating vibratory movement through at least one connection point.

Silo, according to claim 29, characterized in that said mechanism generating vibratory movement is governed from a control center that can also regulate the degree of tension of the laminar wall (60) to which it is applied.

31. Silo, according to claim 26, characterized by said deposit comprises a fixed structure, rigid bars forming frames that define a space in the form of a parallelepiped supporting a dispensing device that provides said discharge opening (60), further supporting said structure bar said drums (61, 62) and rollers (64, 65) on which said laminar walls and said rolls extend.

32. Silo, according to claim 31, characterized in that said laminar walls (60) cover the spaces delimited by each frame.

33. Method of storing and regulated supply of lightweight empty containers (A) by means of a silo of the type comprising a large tank (1) provided with a loading inlet (31) at the top, and a bottom (32) with at least one discharge opening (2) adjustable in its lower part, whose method is characterized in that said tank (1) is subdivided into enclosures (B) superimposed by means of retractable support planes, whose enclosures (B) are filled superiorly by gravity, being said support planes provided with independent means for selectively communicating with each other, at a desired moment, two of said enclosures (B), the height (H) of said enclosures (B) being adequate to the minimum value of the maximum fall height free or the maximum stacking height capable of resisting a predetermined type of container (A) without deteriorating, always starting the feeding of said tank (1) by loading the enclosure located more than The first level, being this one incommunicado with respect to the next one and always realizing the discharge of any enclosure communicating it with the immediately inferior enclosure being this empty, at least in part, and incommunicado with the following one, except when the immediately inferior enclosure is the enclosure situated at the level lower, which is delimited inferiorly by said bottom (32) and said adjustable discharge opening (2), in which case said discharge opening (2) may be closed, for storing containers (A), or open to an extension selected, for a regulated supply of said containers (A).